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[TowerTalk] HF problem

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Subject: [TowerTalk] HF problem
From: (James Sawyer)
Date: Tue, 7 Dec 1999 21:29:17 -0800
I have notice several signals on all bands that have the same MO.   Helping
a few we discovered that the VSWR was just high enough to start the radio to
shut down its power.   When this is at voice rates it will cause the audio
to sound like distorted audio.  That is because it is distorted.   The fix
is to make sue that your antenna systems are as good as you can get them.
Also use a antenna tuner to make sure the transmitter is looking into a good

I also can say that I had a balun problem and a RFI problem that did cause
audio distortion.   A lot of times you can move the mic or mic cord to
increase or decrease the distortion.   I the old AM days you just got high
pitch feedback.   Good luck in correcting your problems.

-----Original Message-----
[]On Behalf Of
Sent: Tuesday, December 07, 1999 12:28 PM
Subject: Re: [TowerTalk] HF problem

 In a message dated 99-12-07 12:45:05 EST, writes:

 > >     I recently installed a Hy-gain TH5 on my 90 foot tower and have a
 > Kenwood TS-450.  I received reports of a strong signal but
 >that my voice sounds distorted.
       I don't think that anything you do to the antenna will affect your
 transmitted audio. The comment about RFI seems most likely. Get a local to
 listen to your signal on different bands and start isolating the problem.

 Cheers,   Steve  K7LXC
    I would disagree and there is a simple process to track it down. With no
or poor baluns or just excessive RF pick up on the coax shield below the
balun being carried into the shack, RF can get into the mike circuit and
create "RF Distortion" in the audio in particular with the processor on.
I've had it happen.  Use a good or a different balun.  Or take the DE down
and do a complete clean job on it inside and out of the tubing.  One bad
connection can upset the DE currents even with a good balun.  The DE is
grounded to the boom and can excite it, the mast and coax shield.  Try
different mikes and or another similar rig with your mike and or other rigs.
Ground the rig.  If it has a monitor circuit, listen for the distortion or
changes with each other remedy.  Try it into a dummy load and monitor the
audio in the monitor circuit or another rig in the shack with and without
processor on.

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